Synthesis and characterization of soluble aromatic polyurea‐amides from new N,N′‐‐dimethyl‐N,N′‐bis(aminophenyl)ureas and aromatic dicarboxylic acid chlorides

Abstract

SYNOPSISAromatic polyurea-amides having inherent viscosities of 0.36-0.67 dL/g were synthesized by the low temperature solution polycondensation of new N,N'-dimethyl-N,N'bis(aminopheny1)ureas with various aromatic dicarboxylic acid chlorides. All the polymers were amorphous, and most of them were soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide (DMAc), m-cresol, and pyridine. Some of the polymers could be cast from the DMAc solutions into transparent and flexible films having good tensile properties. The glass transition temperatures of the polyurea-amides obtained from the bis(4-aminophenyl)-substituted ureas were 244-272°C. The temperatures of 10% weight loss under nitrogen of the polymers were in the range of 430 and 480°C. 0 1995 John Wiley & Sons, Inc.

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